Connected: An Internet Encyclopedia
RFC 922 - 6.2. Multi-subnet broadcasts

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### 6.2. Multi-subnet broadcasts

When a gateway receives a broadcast meant for all subnets of an IP network, it must use the Reverse Path Forwarding algorithm to decide what to do. The method is simple: the gateway should forward copies of the datagram along all connected links, if and only if the datagram arrived on the link which is part of the best route between the gateway and the source of the datagram. Otherwise, the datagram should be discarded.

This algorithm may be improved if some or all of the gateways exchange among themselves additional information; this can be done transparently from the point of view of other hosts and even other gateways. See [4, 3] for details.

Next: 6.3. Pseudo-Algol Routing Algorithm

Connected: An Internet Encyclopedia
RFC 922 - 6.2. Multi-subnet broadcasts